Microstructure and mechanical properties of Be–Al alloy fabricated by laser solid forming

Abstract

The microstructures and tensile mechanical properties of thin-walled Be-38 wt%Al samples produced by laser solid forming (LSF) are investigated. The results show that no cracking or significant porosity is observed in the thin-walled samples. The microstructure of the LSFed Be–Al alloy is primarily composed of columnar Be grains delineated by continuous Al networks. The columnar Be grains show almost the same crystallographic orientation, in which the preferred growth direction is the <0001> direction inclined towards the scanning direction at an angle of approximately 70°. The widths of the Be columnar grains gradually increase as the deposition height increases. The LSFed Be–Al alloy shows anisotropic tensile properties, exhibiting higher ultimate tensile strength and yield strength but smaller elongations for the longitudinal specimens compared to the transverse specimens. BeO and Al2O3 particles are observed to be primarily distributed at the Be/Al interface, resulting in a lack of bonding or cracking during the tensile test.